def sequence(n):
    if n==0:
        return 1
    else:
        return sequence(int(n/3))+sequence(int(n/5))
    
def com(a,b):
    N=1
    i=b
    if a==b:
        return 1
    else:
        while i>1:
            N*=a
            a-=1
            i-=1
        while b>1:
            N/=b
            b-=1
        return N
    

N=int(input())
i=0
j=0
M=N
total=0
while M>1:
    M=M/5
    i+=1

while j<=i:
    total+=com(i,j)*sequence(int(M*((5/3)**j)))
    j+=1
    



print('%d'%total)